Question on USGS bathymetry files
5 years 7 months ago #6910
Total newbie at this. I've messed around a little bit on my own with no success. Can anyone tell me if it's possible to generate shading or contour maps for a Lowrance HDS Gen 3 unit from either:
WinZip ArcInfo Coverage - PC/NT platform data: The bathymetry files were created using the raster module (GRID) for the GIS software program ArcInfo (on a UNIX platform). The Zip download option is used to access a sel uncompressing executeable file created using the program WinZip. When uncompressed, a directory containing two subdirectories will be created. The two subdirectories (an Info and a theme directory) together make up the Grid coverage. If you want to store these data in another directory that already contains an ArcInfo coverage or a Grid coverage, you will need to use the ArcInfo program to copy these data. If you use a file management window to "copy" the data, the indexing link between the coverage and it's info directory will be broken (possibly corrupting 2 or more coverages).
ArcView Shape Files: The ArcView shape files are a simplified version of the raster data, with depth ranges rather than continuous depth values. These shape files contain double precision data that was compressed using the software program WinZip. These files are stored as PC/NT format data,
These are for river maps:
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